lostpunk5545
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Ok you're going to make me type a lot here...
This is an excerpt from a supplement that came with an issue of New Scientist (Issue 2468). The article is entitled When Time Began...
This quote from the same article may also help you:
I just typed like 700 words so that had better have been helpful. It's hard to find an explanation that is much clearer than that. If all that sounds like a load of hogwash here is a very brief summation of the evidence for all this found today:
This is an excerpt from a supplement that came with an issue of New Scientist (Issue 2468). The article is entitled When Time Began...
...the theory of relativity permits space and time to possess a variety of boundaries or edges, technically known as singularities. One type of singularity exists in the centre of a black hole. Another corresponds to a past boundary of space and time at the big bang. The idea is that, as you move backwards in time, the universe becomes more and more compressed and the warping of space-time escalates without limit, until it becomes infinite at a singularity. Very roughly, it resembles the apex of a cone, where the fabric of the cone tapers to an infinitely sharp point and ceases. It is here that space and time begin.
Once this idea is accepted, it is immediately obvious that the question "What happened before the big bang?" is meaningless. There was no such epoch as "before the big bang", because time began with the big bang. Unfortunately, the question is often answered with the bald statement "There was nothing before the big bang", and this has caused yet more misunderstandings. Many people interpret "nothing" in this concept to mean empty space, but let's be clear: space did not exist either prior to the big bang.
Perhaps "nothing" here means something more subtle, like pre-space, or some abstract state from which space emerges? But again, this is not what is intended by the word. As Stephen Hawking has remarked, the question "What lies North of the North Pole?" can also be answered by "nothing", not because there is some mysterious Land of Nothing there, but because the region referred to simply does not exist. It is not merely physically, but also logically, non-existent. So too with the epoch before the big bang.
People tend to get very upset when told about this. They think they have been tricked, verbally or logically. They suspect that scientists can't explain the ultimate origin of the universe and are resorting to obscure and dubious concepts like the origin of time merely to befuddle their detractors. The mindset behind such outraged objection is understandable: our brains are hard-wired for us to think in terms of cause and effect. Because normal physical causation takes place within time, with effect following cause, there is a natural tendency to envisage a chain of causation stretching back in time either without any beginning, or else terminating in a metaphysical First Cause, or Uncaused Cause or Prime Mover.
This quote from the same article may also help you:
A helpful, albeit two-dimensional, analogy for the expanding universe is a balloon with paper spots stuck to the surface. As the balloon is inflated, so the spots, which play the role of galaxies, move apart from each other. Note that it is the surface of the balloon, not the volume within that represents the three dimensional universe.
Now, imagine playing the cosmic movie backwards, so that the balloon shrinks rather than expands. If the balloon were perfectly spherical (and the rubber sheet infinitely thin) at a certain time in the past the entire balloon would shrivel to a speck. This is the beginning.
Translated into statements about the real universe, this describes an origin in which space itself comes into existence at the big bang and expands from nothing to form a larger and larger volume. The matter and energy content of the universe likewise originates at or near the beginning, and populates the universe at all times. Again, it must be stressed that the speck from which space emerges is not located in anything. It is not an object surrounded by emptiness. It is the origin of space itself, infinitely compressed. Note that the speck itself does not sit there for an infinite duration. It appears instantaneously from nothing and immediately from nothing and immediately expands. This is why the question of why it does not collapse back to a black hole is irrelevant. Indeed, according to the theory of relativity, there is no possibility of the speck existing through time because time itself began at this point.
I just typed like 700 words so that had better have been helpful. It's hard to find an explanation that is much clearer than that. If all that sounds like a load of hogwash here is a very brief summation of the evidence for all this found today:
Direct evidence for a cosmic origin in a big bang comes from three observations. The first, and most direct, is that the universe is still expanding today. The second is the existence of a pervasive heat radiation that is neatly explained as the fading afterglow of the primeval fire that accompanied the big bang. The third strand of evidence is the relative abundances of chemical elements, which can be correctly accounted for in terms of nuclear processes in the hot dense phase that followed the big bang.
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